The only thing that makes me scratch my head is, the game came out in 2002, and is a prequel. One of the worlds is a Lilo and Stitch world. Now, if the original game came out in 02, and you assume had been in production/planning stages since maybe 2000, and Lilo and Stitch came out 2002. How could a prequel involve a property that came out after the original game? Maybe the game franchise is set in the the future? Or maybe there’s time hopping at work?
Well, assuming Stitch’s world was destroyed before appearing in KH2, it makes sense. Why didn’t you get to visit his world in KH2, but could use as a Summon? A-ha…!
Or, they just couldn’t secure the rights to use L&S before this game.